1. Field of the Invention
The invention relates to new disperse-reactive dyes and to their preparation. More specifically, the present invention relates to the disperse-reactive dyes with acetoxyethylsulfone and vinylsulfone as reactive groups represented by the formula (1) and (2),AcOCH2CH2SO2—Ar1—NH2  (1)H2C═CHSO2—Ar2—NH2  (2)wherein each of Ar1 and Ar2 is aryl or benzothiazole.
As used herein, “AcO” represents an acetoxy group.
According to the invention, there are provided water insoluble disperse-reactive dyes expressed by the formula (3) and (4). wherein each of Ar1 and Ar2 represents aryl or benzothiazole group, and each of R, R1, R2, and R3 independently represents hydrogen, alkyl, alkoxy, cyanoalkyl or aminoacetyl group.
2. Description of the Related Art
For dyeing of wool, silk, nylon and polyurethane, there have been generally employed water-soluble dyes such as acid dyes, metal complex dyes and reactive dyes. The largest number of acid and metal complex dyes are constituted azo dyes, which are capable of releasing some carcinogenic aromatic amines as a result of the reductive cleavage of azo bonds. It has been also reported that azo dyes can be metabolically cleaved by enzymatic reduction in the human organs.
In 1995, the German law on harmful substances listed 20 hazardous aromatic amines, and prohibited the import as well as selling of textiles and goods dyed with dyestuff based on cleavable those amines. Recently, the environmental protection are becoming important concern, therefore the use of metal complex dyes including heavy metals has been strictly regulated. The conventional acid and metal complex dyes have high water solubility, and they cause dyeing wastewater containing a high concentration of residual dyes. And also those dyes give poor washing fastness. The conventional reactive dyes exhibit very good washing fastness by forming a covalent bond between fiber and dye. However the dyeing with reactive dyes is carried out under alkali condition, it may cause degradation of wool or silk fiber.
In 1960, the water-insoluble disperse-reactive dyes were introduced by ICI (Imperial Chemical Industries Ltd.) as Procinyl dyestuff.
In present several disperse-reactive dyes are commercially available and the research is continuously progressing.